1. Field of the Invention
The present invention relates to thread inserting and braking mechanisms for knotting apparatuses, and more particularly to a mechanism which inserts the threads into a knotting apparatus and cooperates with a braking mechanism to retain the threads therein when the threads are acted upon by the thread lifting mechanism.
2. Description of the Prior Art
In practice, a plurality of spooling machines are placed in close proximity to each other. Generally, one knotting apparatus is utilized for a plurality of these machines and is moved from one machine to another as required. The present invention is utilized on a knotting apparatus of this type, which services a bank of spooling machines. The knotting apparatus and thread inserter and braking mechanism of the present invention is affixed to a spooling machine, operatively coupled thereto and derives its energy for operation from a backwardly and forwardly moving shaft provided therein.
The knotting apparatus of the present invention provides a fisherman's knot, which includes two loops formed separate from each other with the remaining thread ends cut off. The loops are then pulled together to form a knot. In order to obtain adequate cutting pressure, the thread ends are clamped in binding heads which also include the cutting mechanisms. Thread lifters provide the appropriate thread tension which pull the loops together and form a tight knot.
Prior art knotting mechanisms form loops on both binding heads and the threads are clamped therein in order to enable them to be severed. The arms of the thread lifting mechanism, located on the side of the binding heads, provide sufficient thread tension to pull the loops tight on the binding head and thereafter remove them therefrom. In providing the tension while the threads are on the binding heads and thereafter pulling the threads off, an undesirable knotting effect occurs, particularly in soft threads, in the area of the loops. This knotting or tangling effect is so undesirable that tensioning the thread to form the finished knot generally causes thread breakage. In some cases, it merely prevents the knot from being tightened so that an unreliable knot is formed. This is detected by a thread tester, in the further operation of the spooling machine, and the thread is caused to be cut and re-knotted.
In other known knotting devices, the loop is formed in a relatively loose fashion on the binding heads. With this type of knotting mechanism, a specially driven and specially steered thread lifter disposed between the binding heads is used to remove the clamped threads therefrom in order that they may be pulled together thereafter by the two arms of another thread lifter disposed outside of the binding heads. However, this requires a specially driven and steered thread lifter located between the two binding heads and generates longer thread ends on a finished knot.
The present invention overcomes the shortcomings of the prior art by providing a thread inserter and braking mechanism which is provided with a pair of arms disposed external to and on either side of the binding heads and operates in combination with a pair of thread brake pads and a thread lifter, which has a pair of arms disposed on either side of the binding heads, thereby permitting the thread loops to be removed from the binding heads at the same time the threads are firmly pulled together.